The invention relates to a device for implanting radioactive seeds in an animal body through a number of needles, said number being one or more, implanted in the animal body.
The invention also relates to a method for implanting radioactive seeds in an animal body through a number of needles, said number being one or more, implanted in the animal body.
A device for implanting radioactive seeds in an animal body is known from Journal of Brachytherapy International 1998;14:21-27. Therein is described a device in which under ultrasound guidance using an ultrasound probe and using a first template implant needles, hereinafter needles, are placed in a prostate gland. Under fluoroscopy the positions of the needles are checked. For every individual needle the length of the train of seeds is determined. The trains of seeds are placed into the needles with custom-made stylets. Thereafter a second template is attached to a stepping unit in the same way as the ultrasound probe. The ends of the stylets are placed in the second template at the same positions as the needles in the first template. The correct distance between the second template and the ends of the needles is established and the needles are retracted over the stylets manually.
The described method of implanting is cumbersome in that a lot of specialized and delicate tasks have to be fulfilled manually. Acting like this it is not possible to reach a high degree of accuracy in the placement of the seeds. The determination of the desired placements of the seeds can be done with very high accuracy based upon the known physics of the radioactive radiation emitted by the seeds and the geometry of the prostate gland. Such determination of desired placement usually is done by means of a computer programmed with a known therapy planning program. One such program is marketed under the trademark PLATO by Nucletron BV of the Netherlands. Nevertheless the manual placement of the seeds makes it necessary to recheck the number of seeds introduced and if necessary to introduce additional seed trains.
It is an object of the invention to provide a device for implanting radioactive seeds in an animal body through a number of needles implanted in the animal body, the number being one or more, the device comprising electronic control means, loading means connected to the electronic control means for arranging a the number of trains of the radioactive seeds in a the number of channels within the loading means in response to the electronic control means; drive means connected to the electronic control means for extending a wire to push the trains of radioactive seeds from the channels through one or a the number of tubes coupled at a first end to the channels into the implant needles coupled to the second end(s) of the tube(s) in response to the electronic control means; and retracting means connected to the implant needles for retracting each of the implant needles from the animal body while the pushing wire is in an extended position to thereby implant the radioactive seeds.
It is a further object of the invention to provide such a device wherein the loading means further includes a multichannel holder connected to the electronic control means and wherein the control means controls the loading means to arrange a train of seeds in a separate channel in the multichannel holder for each of the implant needles.
It is a still further object of the invention to provide such a device wherein the retracting means are electronically controllable and are connected to and operateable in response to signals from the electronic control means.
It is a further object of the invention to provide such a device wherein the tube(s) comprise a first part and a second part, which first and second parts overlap, the first part being connected to the loading means and the second part being slideable relative to the first part and coupled to the implant needles.
It is a still further object of the invention to provide a seed loading module comprising electronic control means, the seed loading module further comprising loading means connected to the electronic control means for in response to the control means arranging a number of trains of radioactive seeds, the number being one or more, in a the number of channels in a removable multichannel holder within the seed loading module, the seed loading module including a supply container having a reservoir for radioactive seeds and drive means connected to the electronic control means for extending a wire to push radioactive seeds from the supply container into the channels.
It is a still further object of the invention to provide a seed implanting module comprising electronic control means, the seed implanting module further comprising receiving means for receiving a number of trains of radioactive seeds, the number being one or more, in a the number of channels in a removable multichannel holder, drive means connected to the electronic control means for extending a wire to push the trains of radioactive seeds from the channels through one or a the number of tubes coupled at a first end to the channels into the implant needles coupled to the second end(s) of the tube(s) in response to the electronic control means; and retracting means connected to the implant needles for retracting each of the implant needles from the animal body while the pushing wire is in an extended position to thereby implant the radioactive seeds.
It is a still further object of the invention to provide a device for implanting radioactive seeds and a seed loading module each further comprising therapy planning means connected to the electronic control means for providing the electronic control means with signals representing a desired arrangement of seeds in a train for each of the needles, and wherein the electronic control means controls the loading means in response to the signals from the therapy planning means.
It is a still further object of the invention to provide such a device wherein blood contaminatable parts are removable.
It is also an object of the invention to provide a method for implanting radioactive seeds in an animal body through a number of needles implanted in the animal body, the number being one or more, the method comprising: determining a desired pattern of seeds and inputting the desired pattern into an electronic control device; arranging a train of seeds in a channel in accordance with the desired pattern for each of the implant needles in response to a signal from the electronic control device; extending a drive wire to push each the trains of seeds from its channel through a tube and into a corresponding one of the implant needles in accordance with the desired pattern in response to a signal from the electronic control device and retracting each of the implant needles while holding the drive wire in an extended position to thereby implant the trains of seeds in the animal body in the desired pattern.
The invention shall now be described in more detail with the help of the accompanying drawings.